Unsupported class file major version 57

[prkos]

I can't get it to work. Am I doing something wrong or maybe I don't meet the requirements?

I'm attaching the debug (replaced my username in the text file).

debugM24.txt

$ java -version
openjdk version "1.8.0_282"
OpenJDK Runtime Environment (build 1.8.0_282-8u282-b08-0ubuntu1~20.04-b08)
OpenJDK 64-Bit Server VM (build 25.282-b08, mixed mode)

[jonhnet]

Hi prkos,

Hmm, it's working for me, and my runtime environment matches yours:

$ java -version 
openjdk version "1.8.0_282"
OpenJDK Runtime Environment (build 1.8.0_282-8u282-b08-0ubuntu1~20.10-b08)
OpenJDK 64-Bit Server VM (build 25.282-b08, mixed mode)

The gradle command needs javac since the git has only source, no jar. Your debug log suggests you have it, but just in case:

$ javac -version 
javac 1.8.0_282

Beyond that I'm a bit mystified.
Happy to help you try to debug further, though. It definitely smells like a java configuration problem.

[prkos]

Wow speedy gonzales :D

mine shows up a bit different:

$ javac -version 
javac 13.0.2

[prkos]

~$ which javac
/usr/bin/javac

~$ ls -lsah /usr/bin/javac
0 lrwxrwxrwx 1 root root 23 velj 19  2020 /usr/bin/javac -> /etc/alternatives/javac

~$ ls -lsah /etc/alternatives/javac
0 lrwxrwxrwx 1 root root 37 velj 19  2020 /etc/alternatives/javac -> /usr/lib/jvm/java-13-oracle/bin/javac

~$ cd /usr/lib/jvm/java-13-oracle/bin/
/usr/lib/jvm/java-13-oracle/bin$ ./javac -version
javac 13.0.2

[prkos]

I changed it to javac 1.8.0_282 with sudo update-alternatives --config javac but I'm still getting build failed.